X-ray tube



T. B. RIDER. X-RAY T UBE.

APPLICATION FILED IAN. I8. I9I8.

' 1,310,714. Patented July 22,1919;

THOMAS B. RIDER, OF LOS ANGELES, CALIFORNIA, ASSIGNOR F ONE-HALF TOADOLPHE DANZIG-ER, OF Lo ANGELES, CALIFORNIA.

X-RAY TUBE.

Application filed January 18, 1918.

' citizen of the United States, residing at Los Angeles, in the countyof Los Angeles and State of California, have invented a new and usefulX-Ray Tube, of which the following is a specification.

This invention relates to X-ray' tubes in .which the electrons travel athigh velocity between thecathode and the target formed by the anode.

One object of the invention is to prevent overheating andmelting of themetal on the surface of the target or anode by providing means forchanging the focal spot, when the tube is being used with shortinterruptions for a number of operations.

Another object is to lengthen the life of such targets or anodes byproviding separate independent focal spots in the surface of the anodeso that a deforming of the surface of one spot cannot influence any ofthe other spots.

Another object is to provide means of holding the cathode and anode insuitable relationso that a stream of cathode rays can implnge on thesurface of the anode.

Other objects will appear from the accompanying drawing as well as fromthe following description and appended claims.

In the drawing- Figure 1 is a fragmentary longitudinal sectional View ofthe adjusting means for changing the relation between the cathode andthe anode.

Fig. 2 is a fragmentary side elevation of the anode showing the outlineof inserted material in the surface of the anode.

Fig. 3 is the front elevation of the anode, several separate insets inthe surface of the anode being illustrated in the manner I prefer.

Fig. 4 is a front elevation of a rotating target for the anode/ Fig. 5is a fragmentary longitudinal section through the anode slightlymodified with the rotating target in position.

Similar numbers refer to similar parts throughout the several views.

In Fig. 1, 4t designates the X-ray tube and 5 the extension tube, whichare usually made of glass. The stem 6 is fused into the end 7 of thetube 6 projecting practically concentrically into the X-ray tube. Thecathode 8 is slidingly and turnably mounted on the stem 7 being providedwith an extension 9, forming the housing for the operating mech-Specification of Letters Patent.

Patented July 22, 1919.

Serial No. 212,529.

anism. The cathode with extension being preferably made of aluminum,which can naturally not be influenced by a magnet, I prefer materialwhich can be influenced by a magnet for the operating parts for which arecess 10 is provided in the extension of the cathode. Lugs 11 areprovided at a suit able place for the blocks 12 and 13. These blocks arepreferably made of steel or other suitable material which can beinfluenced by a magnet, and being pivotally connected with the lugs, theblocks can naturally be drawn toward the wall of the glass tube 5 byholding ,a magnet on the outside of the glass tube. The rings 14 and 15pivotally connected with each other at 16 are disposed on the stem 6having holes 17 of a size slightly larger than the diameter of the stemso that, when in the position shown, the edges of the material near theholes set or clamp themselves tightly to the stem (3 while in acompressed position, illustrated in dotted'lines at 18, the holes beingnaturally large enough to easily slip over the stem to any desiredposition. Bosses '19 are provided on the rings 14 and 15 at suitableplaces forming the support for the spring 20.

Holding a magnet to the outside of the extension tube 6 near the blocks12 and 13, naturally causes a drawing of the blocks, with their freeends 21 sliding along the outer flat surfaces of the rings, toward theedges 22 to the position indicated in dotted lines at 23, bringingtherings to the compressed position indicated in dotted lines at 18', inwhich position therings can .freely be moved, slipping over the stem asdescribed above, to be set on the stem in any desired with the extension9 and with the embodied To allow and assure a fpcusing of the cathode tothe center of each of the several insets, the stem 6 is made with acorrespondstem, the setting or clamping-of the operatremoved from nearthe extension tube 5 Causing the releasing'of theblocks thereby '25 Itwill easily be understood that such remg means to the stem will bepossible as.

long as the upper and lower edges in the holes engage with the stemwhich will be the case with square or oval holes as l as two flat sidesare provided in the holes.

. After having the rings contracted or com pressed as described aboveand set the cath-' ode to a position desired, the magnet is allowing thespring to press the rings back to the engaging position illustrated inFig. 1.

leasing can be effected to focus the cathode to any of the insets in thesurface of the anode, and, if not quite to the center of the insets, thesuitably shaped holes '17 will settle on the correspondingly shaped stem6 to bring the focus from'the cathode to the center of one of theinsets.

In the slightly modified construction of theanode illustrated in Figs. Land 5, the inserts 25 are embodied in an extra p'la'te26, which isrotatably mounted on the front of the anode 24, the boss 27 beingprovided on of the weight'onthe target-plate.

.is desirable to change the position of the the target-plate 27 turnablyfitting in a suitable hole or recess inthe anode. This targetplate 26 isalso provided-with balancing ball .or weight extensions 28 for changingthe position of the target-plate by the gravity lnce it target-plate 26always a certain distance, that is from one inset to another to bringthe focus of the cathode to one of the insets, a tumbler or locking pin29 is slidingly embodied in the anode being pressed by the spring 30into one of the notches or recesses 31 in the target-plate 26-. Suchnotches or recesses- 31 are naturally arranged corresponding to theinsets 25 to assure a proper position for the insets in'relation to thefocus from the cathode, as will easily be understood.

If desired to change the focus from'the cathode to a new, or from oneinset to another inset, the whole X-ray tube is shaken anode.

enough to cause the Weight extension 28 .to

an operation as is required when changing the focus by turning thecathode in the manner described in relation to Fig. 1.

As illustrated in Fig. 1, the focusing face.

of the cathode naturally must be arranged eccentrically to the bore inthe cathode, or the center of the focusing face eccentrically to thecenter of the supporting stem 6, so as g to bring the focus to thedifferent insets when turning scribed above.

Having thus described my invention, I claim: v

1. In an X-ray tube an anode having a suitable number ofindependentinsets, and a cathode having means for focusing the cathodetoward any of the insets in the the cathode on the stem asde- In anX-ray tube, a cathode comprising a body having a concentric bore andhaving a focusing face transverse to the bore with the center of the.focusing face eccentric to the center of the bore in the body, a stem inthe tube forming a support for the cathode; the cathode being turnablyand slidably disposed on the stem, and

I clamping members engaging with the bod of the cathode having means toengage wit ,the stem for holding the cathode in focusing position, theclamping members also adapted for moving the cathode on the stem. 3. 'Inan X-ray tubean anode havin a suitable number of insets, a cathodehavlng means for focusing the same toward any of the insets in theanode, and a stem forming the support for the cathode having a num-v berof flat surfaces longitudinally to the ste corresponding to the numberof the insets in. the anode.

4:. In an/X-ray tube an-anode having a suitable number of insets ofsuitable material to withstand the stream of cathode rays consisting ofelectrons traveling at high velocity and having also means for changingthe focus of the cathode to any of the insets in the anode.

.In testimony whereof I hereunto affix my signature in the presence oftwo witnesses.

- THOMAS E. RIDER. Witnesses:

C. M. ENNS, M.- G. FERRAHAN.

